(a) Field of the Invention
The present invention relates to an engine block adopting an improved cooling system capable of efficiently cooling the cylinder block so as to improve engine performance.
(b) Description of the Related Art
An engine block of an automobile engine is a casting with appropriate machined surfaces and threaded holes for attaching a cylinder head, main bearings, oil pan, and other units.
Cylinders are openings of circular cross section that extend through to the upper portion of the block with interior walls bored and polished to form smooth, accurate surfaces. The cylinders of heavy-duty engines are usually fitted with removable liners made of metal that is more wear-resistant than the block casting material.
To carry away excessive heat, an engine is provided with a series of channels cast into the engine block and cylinder head, surrounding combustion chambers with circulating water or other coolant.
The channels are formed, particularly between the cylinders, using drilling or saw-cutting methods as well as through a casting process. Using drilling or saw-cutting methods requires 7 mm of inter-cylinder distance, and using casting methods, 12 mm are needed.
Recently, the inter-cylinder distance has tended to become shorter so as to comply with minimizing engine size, and furthermore, aluminum cylinder blocks have extremely small inter-cylinder distances of 3 mm, which cause difficulty in forming coolant channels between the cylinders.
The present invention has been made in an effort to solve the above problems of the prior art.
It is an object of the present invention to provide an engine block having coolant channels between cylinders with narrow inter-cylinder distance for efficiently cooling the engine block.
To achieve the above object, an engine block having a cooling system according to a preferred embodiment of the present invention comprises a body, a plurality of cylinder bores formed on the body, cylinder liners each coaxially fitted in a corresponding cylinder bore, and at least one coolant channel formed between the cylinder bores, wherein each cylinder liner has recesses on an outer surface facing other cylinder bores for securing space for forming the coolant channels.